Track layer for trucks



C. W. GREGORY.

TRACK LAYER FOR TRUCKS.

APPLiCATlON FILED JULY 21,1919.

LitQ LSZO. Patented Jan. 24, 1922 4 SHhEfS-SHEET 1.

3 INVENTOR CARL W GREGORY A TTOR NE 3" c. w. GREGORY. TRACK LAYER FOR TRUCKS.

APPLECATION FILED JULY 21,1919.

Patented Jan 24, 1922'.

4 SHhETS-SHEET 2.

NUSU

INVENTOR Om W 6175609) A TTORNE Y C. W. GREGORY.

TRACK LAYER FOR TRUCKS.

APPLICATION FILED JULY 21.1919.

: AJQ FL 52m, Patented Jan. 24 1922.

4 SHEETS-SHEET 3- IN VE N TOR C404 14/. GREGORY A TTORNE Y C. W. GREGORY. TRACK LAYER FOR TRUCKS.

APPUCATION FILED JULY 2|,1919. 1,404,520. 4 Patented Jan 24, 1922.

4 SHHETSSHEET 4.

INV EN TOR C401 W 6/?560/PY BY A TTOR NE Y CARL W. GREGORY, OF PE'IALUMA, CALIFORNIA.

PATENT OFF ICE.

TRACK FOR TRUCKS.

Specification of Letters Patent.

Patented Jan. 24, 1922.

Application filed July 21, 1919. Serial Ho, 812,441.

To all whom it may concern:

Be it known that I, CARL W. GREGORY, a citizen of the United States, and a resident of the city of Petaluma, county of Sonoma, State of California, have made a new and useful inventionto wit, Track Layers for Trucks; and I do hereby declare the following to be a full, clear, concise, and exact description of the same.

The present invention is an attachment for motor trucks, and contemplates the use of tracklaying units which are substituted for the rear or drive wheels of said truck.

The primary object of the invention is to provide attachments of new and novel construction as regards the spring suspension. The novelty in construction and operation of my device lies in the double spring suspension. The forward springs being carfied by a truss, as hereinafter described, cooperate with the spring suspension already installed on the truck, and through the agency of both of the interposed'springs between both ends of tracklaying attachment and the'load, provide means which will operate in a reverse direction, and which will act while being driven in either direction independently of the inclination of the body of the truck.

A further object is to construct and apply track laying units in such a manner that the center of gravity of the load carried by said units may be automatically'shifted with respect to its bearing oint on the truck; thereby causing the veh cle to negotiate changes inits plane of operation without interfering with the forward movement of the track laying units.

In-this specification and the annexed drawings, the invention-is illustrated in the form considered to be the best, but it is to be understood that the invention is not limited to such form, because it may be embodied in other forms and it is also to be under: stood that in and by the claims following the description it is desired to cover the invention in whatever form it may be embodied.

In the drawings:

Figure 1 is a top plan view of a truck.

with my invention applied" thereto.

Figure 2 is a side elevation of one of my track laying attachments for a truck.

Figure 3 is a cross section taken on th line III-III of Figure 5.

Figure 4 is a detail view showing the manner of attaching the forward end of a track laying unit to a truck (only one attaching means being shown).

F igure 5 is a side elevation of a truck of conventional type with my attachment installed thereon.

Referring to the drawings in detail, the numerals 1 and 2 indicate the sills of a motor truck, while the numerals 3, 4, 5, 6 and 7 refer to cross braces connecting said sills. This frame so formed carries a power unit 8 having a shaft 9 extending rearwardly. The usual front axle 10'is provided which carries wheels 11 and 12 capable of being steered. This axle is secured to the front of the vehicle by suitable springs, not shown.

At 13, I have'shown a rear axle housing having the usual differential and enclosing a horizontal shaft which secures itspower from the propeller shaft 9 and suitable dif ferential gears. Springs 14 and 15 are supported by the axle housing and have suitable connections with said frame.

All of the description thus far refers to a standard type of truck (as differentiated from tractors) which is adapted to haul variouscommodities, and is the type of truck ing units in substitution for the usual wheels. These track laying units are here shown .by the numerals 16 and 17. One of these track upon which I wish to employ my track lay- I laying units is best shown in side elevation These channel irons are attached at their 7 forward end by a casting 2O suitably bolted thereto. The forward ends sup ort the lower halves 21 of keeper plates. hese keeper lates have ca s22 and are slidably held By yokes 23. hese plates are in axial alignment and fixedly secured to a short horizontal shaft 24 carrying a flanged hub 25 rotating freely thereon, which carries a sprocket wheel rim 26. The sprocket wheel rotates between the ends of the channel irons 18 and 19. i The opposite ends of these channel irons carry the lower portions of bearing blocks 27 (Figure 3) to which are attached bearing caps 28 by means of U bolts 29 passing over the same and engaging the underside of the channel irons 18 and 19. The bearings thus formed uponeach channel iron are in axial alignment and are adapted to carry a tubular member 30 having a radical flange 31 whichis approximatel in the center of the tubular member. aid flange carries a sprocket wheel rim 32 suit-- ably secured thereto. This sprocket wheel rim may be made integral or detachable, as shown at 33. This tubular member 30 is provided at the end adjacent the truck with p a flange .34, and at its opposite end with a flange 35. the channel members 18 and 19 are keeper plates 36, 37 and 38 (Figure 2) which rigidly secure shafts 39, 40 and 41 upon which are mounted freely rotating idlers 42, 43

and 44, thepurpose of which will be hereinafter seen. Mounted between the bearings 21 and 27 I provide a U-shaped frame 45 upon each channel iron, which is suitably braced by braces 46 and 47. These il-shapedmembers support keepers 48 which are in axial alignment and rigidly secure a shaft 49 upon which is mounted an idler 50. The sprockets 26 and 32 are in alignment so as to accommodate a chain made up of links 51 and 52 carrying treads 53. This endless chain passes over the sprocket .wh'eel 26,'

,er plates 21 forward on their channel bars} thus effecting a tightening of the links coniposing the chain. I

whatis commonly known as a live axle.

is obvious, however, that the same may be employed with trucks of the dead axle type,

as well. as with those termed 'floating, WlthOlltdGPflltiIlg from the spirit of my vention..

In assembling my invention on a motor truck, it is necessary to disconnect the axle shaft drive plate from the hub flange on the rear wheel. The axle shaft, wh1ch is floating, is then withdrawn, after which the lock nuts which secure the wheel to. the shaft housing are removed and the wheel taken oil. I then substitute for these parts renlioved, the assembly shown in Figures 2 an 3.

This is accomplished by sliding the part 30 upon the shaft housing. The lock nuts Bolted to the under sides of which held the wheel in lace are then replaced and tightened. I?

moved. This new axle carries a drive plate having-an outwardl flaring flange which isattached by suita le bolts to the flange 35 a shown. v lleferring now to Figure 4, I provide an I-beam 62 placed horizontally and in transverserelatlon to the sill members 1 and 2. This I-bea-m projects beyond the line of said sills and is attached thereto by, means of bolts63 passing through Z shaped keepers 64 on which. are journalled rollers 65. These rollers contact with the flanges of said sill members and slidably support said I-beam 62. The outer'ends of these I-beams are plovided with adjustment openings 66 whic allow angle members 67 to be moved laterally to accommodate different widths new axle is then inserted in the place of the one re-' of; tread; These angle members 67 carry I vertically adjustable yoke members 68 adjusted through the'medium of bolts 69 and .openings73.' The outer ends of these yoke members are adapted to overlie and underlie the center of the cast members 20, so that a bolt 70 passed through each yoke will pass through said cast members'20. The bolt 70 carries a spring 71 above the member 20 and a spring 72 below said member 20, the purpose of which after described. 3

In vehicles not provided with torque rods 'or truss rods there is a sli ht movement of at the center of said spring.

, .When an .incline or heavy going is encountered, the movement just referred to 7 becomes greater. It is to accommodate this In the present instance, I have shown my track laying units upon a truck havin pivot point for "the units in order that they may have free movement in negotiating rough ground. Theaction of my unit is as follows Referring now to Fi re 5, in which the truck is shown on: love I ound, I wish to describe an action-which is peculiar tothis construction, andwhich is of decided imwill be hereinw ThisI-beam and the yokes at- 'tached thereto also perform another funcortance in my invention. It is a well own fact that in motor truck construction, the forward axlesupports a relativel small proportion of the weight of the loa approximately 20 per cent, study of Figure 5 will show that the greater art of the load, indicated in dotted lines t ereon, would be supported on the rear axle if same were provided with the usual wheels. WVith the unit substituted herein, the weight will be distributed proportionately between said axle and the springs 71. These springs 71 are of sufficient strength to force the tread elements downward to contact with the ground irrespective of the position ofthe body truck.

It results from this construction that should the track-laying element be on hard ground, and the forward wheels encounter soft ground or a depression in the surface and settle slightly, as indicated by the dotted lines, the springs 70 will receive the major portion of the load and act as a fulcrum over which the truck and load is balanced. This action is peculiar to the structure here shown, and is decidedly beneficial. The action described is decidedly perceptible to a rider on the seat of the truck. \Vhe'n the forward wheels encounter soft ground, as before described, the truck settles at the forward end slightly, and is felt to rise as the weight of the load shifts to the spring 70. The driving power of the tracklayers tends to lift the forward end of the truck out of a depres sion rather than to dig deeper as is the case with tracklaying attachments which are pivoted or journalled to the rear axle.

The springs 70 are so arranged that they co-operate with the semi-elliptical springs connected to the rear axle housing in such a manner that this action just described becomes automatic. 7

The advantage in the application of power is obvious, as in negotiating an inclination or in gassing from an up grade to a down gra e the center of the load automatically shifts to a position best suited to the requirements of the tractor element.

Having thus described my invention what I claim as new and desire to secure by Letters Patent ofthe United States is as follows 1. A motor vehicle comprising aframe, a.

tacttherewith, resilient supports connecting the ends of said bar and the forward ends of said units, said supports being capable of carrying the load of said vehicle.

2. A motor vehicle comprising a frame, a motor mounted on said frame, an axle housing resiliently mounted on said frame, an axle carried by said housing and geared to said motor, track laying units pivoted at one end to said housing and driven by said axle, a transverse bar beneath the said frame and in slidable contact therewith, springs interposed between the forward ends of said track laying units and said bar, said springs being capable of supporting the load of the said vehicle, and said springs bein capable of movement independent of that o the said frame. Y

3. A motor vehicle comprisinga frame, a transverse driven axle resiliently mounted on said frame, track laying units pivoted concentrically with said axle, traction mechanismon said units connected .to said axle,

resilient supports interspaced between said vehicle frame and the forward end of said units, said supports being movable longitudinally with relation to said frame and capable of supporting the load on said vehicle.

In testimony whereof, I have hereunto set my hand at San- Francisco, California,

this llth-day of July, 1919.

CARL W: GREGORY.

In presence of- A. J. HENRY. 

